AP BIOLOGY

THE MOLECULAR BASIS OF INHERITANCE

DNA MAKES RNA MAKES PROTEIN

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
Which enzyme is needed to bring free nucleotides to create a new strand of DNA in DNA replication?
A
DNA helicase
B
DNA ligase
C
DNA replicase
D
DNA polymerase
Explanation: 

Detailed explanation-1: -The first nucleotide polymerizing enzyme, DNA polymerase, was discovered in 1957. The free nucleotides that serve as substrates for this enzyme were found to be deoxyribonucleoside triphosphates, and their polymerization into DNA required a single-stranded DNA template.

Detailed explanation-2: -The primary enzyme involved in this is DNA polymerase which joins nucleotides to synthesize the new complementary strand. DNA polymerase also proofreads each new DNA strand to make sure that there are no errors.

Detailed explanation-3: -As the new nucleotides line up opposite each parent strand by hydrogen bonding, enzymes called DNA polymerases join the nucleotides by way of phosphodiester bonds.

Detailed explanation-4: -During elongation, an enzyme called DNA polymerase adds DNA nucleotides to the 3′ end of the template. Because DNA polymerase can only add new nucleotides at the end of a backbone, a primer sequence, which provides this starting point, is added with complementary RNA nucleotides.

There is 1 question to complete.